Autoimmune diseases arise from an inappropriate immune response of the body against substances and tissues normally present in the body. This may be restricted to certain organs (e.g. in autoimmune thyroiditis) or involve a particular tissue in different places (e.g. Goodpasture's disease which may affect the basement membrane in both the lung and the kidney). The treatment of autoimmune diseases is typically with immunosuppression medication that decreases the immune response.
Diabetes mellitus type 1 (type 1 diabetes, T1DM, formerly insulin dependent or juvenile diabetes) is a form of diabetes mellitus that results from autoimmune destruction of insulin-producing beta cells of the pancreas. The subsequent lack of insulin leads to increased blood and urine glucose. The classical symptoms are polyuria (frequent urination), polydipsia (increased thirst), polyphagia (increased hunger), and weight loss. Incidence varies from 8 to 17 per 100,000 in Northern Europe and the U.S. with a high of about 35 per 100,000 in Scandinavia to a low of 1 per 100,000 in Japan and China. Eventually, type 1 diabetes is fatal unless treated with insulin. Injection is the most common method of administering insulin although other methods are insulin pumps and inhaled insulin. Other alternatives are Pancreatic transplants that have been used and also pancreatic islet cell transplantation. Transplantation is experimental yet growing.
Celiac disease is an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward. Symptoms include pain and discomfort in the digestive tract, chronic constipation and diarrhea, failure to thrive (in children), and fatigue, but these may be absent, and symptoms in other organ systems have been described. Vitamin deficiencies are often noted in people with Coeliac disease due to the reduced ability of the small intestine to properly absorb nutrients from food. Increasingly, diagnoses are being made in asymptomatic persons as a result of increased screening; the condition is thought to affect between 1 in 1,750 and 1 in 105 people in the United States. Coeliac disease is caused by a reaction to gliadin, a prolamin (gluten protein) found in wheat, and similar proteins found in the crops of the tribe Triticeae (which includes other common grains such as barley and rye). Upon exposure to gliadin, and specifically to three peptides found in prolamins, the enzyme tissue transglutaminase modifies the protein, and the immune system cross-reacts with the small-bowel tissue, causing an inflammatory reaction. That leads to a truncating of the villi lining the small intestine (called villous atrophy). This interferes with the absorption of nutrients, because the intestinal villi are responsible for absorption. The only known effective treatment is a lifelong gluten-free diet. While the disease is caused by a reaction to wheat proteins, it is not the same as wheat allergy
HLA-DQ2 (DQ2) is a serotype group within HLA-DQ (DQ) serotyping system. The serotype is determined by the antibody recognition of β2 subset of DQ β-chains. DQ2 represents the second highest risk factor for coeliac disease, the highest risk is a close family member with disease. Due to its link to coeliac disease, DQ2 has the highest association of any HLA serotype with autoimmune disease, close to 95% of all celiacs have DQ2, of that 30% have 2 copies of DQ2. Of the DQ2 homozygotes who eat wheat, lifelong risk is between 20 and 40% for coeliac disease. Juvenile diabetes (T1D) has a high association with DQ2.5 and there appears to be link between GSE and early onset male T1D. Anti-tTG antibodies are found elevated in a one-third of T1D patients, and there are indicators that Triticeae may be involved but the gluten protein is a type of globulin (Glb1). Recent studies indicate a combination of DQ2.5 and DQ8 (both acid peptide presenters) greatly increase the risk of adult onset Type 1 Diabetes and ambiguous type I/II Diabetes. HLA-DR3 plays a prominent role in autoimmune diabetes. However, DQ2 presence with DR3 decreases the age of onset and the severity of the autoimmune disorder.
HLA-DQ8 (DQ8) is a human leukocyte antigen serotype within the HLA-DQ (DQ) serotype group. DQ8 is a split antigen of the DQ3 broad antigen. DQ8 is determined by the antibody recognition of 68 and this generally detects the gene product of DQB1*0302. DQ8 is commonly linked to autoimmune disease in the human population. DQ8 is the second most predominant isoform linked to coeliac disease and the DQ most linked to juvenile diabetes. DQ8 increases the risk for rheumatoid arthritis and is linked to the primary risk locus for RA, HLA-DR4. DR4 also plays an important role in juvenile diabetes. While the DQ8.1 haplotype is associated with disease, there is no known association with the DQB1*0305, DQ8.4 or DQ8.5 haplotypes with autoimmune disease; however, this may be the result of lack of study in populations that carry these and the very low frequency. In Europe, DQ8 is associated with juvenile diabetes and coeliac disease. The highest risk factor for type 1 diabetes is the HLA DQ8/DQ2.5 phenotype. In parts of eastern Scandinavia both DQ2.5 and DQ8 are high increases frequencies of late onset Type I and ambiguous Type I/II diabetes. DQ8 is also found in many indigenous peoples of Asia, it was detected early on in the Bedoin population of Arabia where DQ2.5 is frequently absent, and in these instances DQ8 is solely associated HLA in Coeliac Disease.
Crohn's disease, also known as Crohn syndrome and regional enteritis, is a type of inflammatory bowel disease that may affect any part of the gastrointestinal tract from mouth to anus, causing a wide variety of symptoms. It primarily causes abdominal pain, diarrhea (which may be bloody if inflammation is at its worst), vomiting (can be continuous), or weight loss, but may also cause complications outside the gastrointestinal tract such as skin rashes, arthritis, inflammation of the eye, tiredness, and lack of concentration. Crohn's disease is caused by interactions between environmental, immunological and bacterial factors in genetically susceptible individuals. This results in a chronic inflammatory disorder, in which the body's immune system attacks the gastrointestinal tract possibly directed at microbial antigens. There is a genetic association with Crohn's disease, primarily with variations of the NOD2 gene and its protein, which senses bacterial cell walls. Siblings of affected individuals are at higher risk. Males and females are equally affected. Smokers are two times more likely to develop Crohn's disease than nonsmokers. Crohn's disease affects between 400,000 and 600,000 people in North America. Prevalence estimates for Northern Europe have ranged from 27-48 per 100,000. Crohn's disease tends to present initially in the teens and twenties, with another peak incidence in the fifties to seventies, although the disease can occur at any age. There is no known pharmaceutical or surgical cure for Crohn's disease. Treatment options are restricted to controlling symptoms, maintaining remission, and preventing relapse.
Ulcerative colitis (Colitis ulcerosa, UC) is a form of inflammatory bowel disease (IBD). Ulcerative colitis is a form of colitis, a disease of the colon (large intestine), that includes characteristic ulcers, or open sores. The main symptom of active disease is usually constant diarrhea mixed with blood, of gradual onset. IBD is often confused with irritable bowel syndrome (IBS), a troublesome, but much less serious, condition. Ulcerative colitis has similarities to Crohn's disease, another form of IBD. Ulcerative colitis is an intermittent disease, with periods of exacerbated symptoms, and periods that are relatively symptom-free. Although the symptoms of ulcerative colitis can sometimes diminish on their own, the disease usually requires treatment to go into remission. Ulcerative colitis has an incidence of 1 to 20 cases per 100,000 individuals per year, and a prevalence of 8 to 246 per 100,000 individuals per year. The disease is more prevalent in northern countries of the world, as well as in northern areas of individual countries or other regions. Rates tend to be higher in more affluent countries, which may indicate the increased prevalence is due to increased rates of diagnosis. Although ulcerative colitis has no known cause, there is a presumed genetic component to susceptibility. The disease may be triggered in a susceptible person by environmental factors. Although dietary modification may reduce the discomfort of a person with the disease, ulcerative colitis is not thought to be caused by dietary factors. Ulcerative colitis is treated as an autoimmune disease. Treatment is with anti-inflammatory drugs, immunosuppression, and biological therapy targeting specific components of the immune response. Colectomy (partial or total removal of the large bowel through surgery) is occasionally necessary if the disease is severe, doesn't respond to treatment, or if significant complications develop. A total proctocolectomy (removal of the entirety of the large bowel) can be curative, but it may be associated with complications.
Metabolic syndrome is a combination of medical disorders that, when occurring together, increase the risk of developing cardiovascular disease and diabetes. Some studies have shown the prevalence in the USA to be an estimated 25% of the population, and prevalence increases with age. Metabolic syndrome is also known as metabolic syndrome X, cardiometabolic syndrome, syndrome X, insulin resistance syndrome, Reaven's syndrome (named for Gerald Reaven), and CHAOS (in Australia). The exact mechanisms of the complex pathways of metabolic syndrome are not yet completely known. The pathophysiology is extremely complex and has been only partially elucidated. Most patients are older, obese, sedentary, and have a degree of insulin resistance. Stress can also be a contributing factor. The most important factors are weight, genetics, endocrine disorders (such as polycystic ovary syndrome in women of reproductive age), aging, and sedentary lifestyle, (i.e., low physical activity and excess caloric intake). There is debate regarding whether obesity or insulin resistance is the cause of the metabolic syndrome or if they are consequences of a more far-reaching metabolic derangement. A number of markers of systemic inflammation, including C-reactive protein, are often increased, as are fibrinogen, interleukin 6, tumor necrosis factor-alpha (TNFα), and others. Some have pointed to a variety of causes, including increased uric acid levels caused by dietary fructose. Central obesity is a key feature of the syndrome, reflecting the fact that the syndrome's prevalence is driven by the strong relationship between waist circumference and increasing adiposity. However, despite the importance of obesity, patients who are of normal weight may also be insulin-resistant and have the syndrome. An estimated 75% of British patients with type 2 diabetes or impaired glucose tolerance (IGT) have metabolic syndrome. The presence of metabolic syndrome in these populations is associated with a higher prevalence of CVD than found in patients with type 2 diabetes or IGT without the syndrome.
Hypoadiponectinemia has been shown to increase insulin resistance, and is considered to be a risk factor for developing metabolic syndrome. The approximate prevalence of the metabolic syndrome in patients with coronary heart disease (CHD) is 50%, with a prevalence of 37% in patients with premature coronary artery disease (age 45), particularly in women. With appropriate cardiac rehabilitation and changes in lifestyle (e.g., nutrition, physical activity, weight reduction, and, in some cases, drugs), the prevalence of the syndrome can be reduced. Lipodystrophic disorders in general are associated with metabolic syndrome. Both genetic (e.g., Berardinelli-Seip congenital lipodystrophy, Dunnigan familial partial lipodystrophy) and acquired (e.g., HIV-related lipodystrophy in patients treated with highly active antiretroviral therapy) forms of lipodystrophy may give rise to severe insulin resistance and many of metabolic syndrome's components.
For many of these autoimmune disease there is no cure yet. It would be beneficial if the risk of autoimmune disease is reduced, or to treat or ameliorate the symptoms of autoimmune disease.
It has been surprisingly found that peptides selected from a casein hydrolysate reduces the risk of autoimmune diseases.